Wolff-Parkinson-White in a College Athlete: Why Didn't We Pursue an EP Study?

We report the case of a collegiate volleyball player incidentally discovered to have Wolff-Parkinson-White pattern on preparticipation electrocardiogram screening. Noninvasive testing identified a low-risk pathway. By using a shared decision-making process with the athlete, she was ultimately able to successfully complete her senior season without further workup or adverse events. (Level of Difficulty: Intermediate.).

Familial Hypertrophic Cardiomyopathy With Fasciculoventricular Accessory Pathway.

Hypertrophic cardiomyopathy (HCM) is a common but an underdiagnosed condition. Fasciculoventricular bypass tract (FVBT) is rare. Concomitant presence of both conditions is well described in Danon disease. We report a case of familial HCM with FVBT linked to a heterozygous pathogenic variant, c.655G>C (p.Val219Leu), in the cardiac myosin binding protein C3 (MYBPC3) gene. (Level of Difficulty: Advanced.).

Tachycardiomyopathy Caused by a Pseudo-Ventricular Tachycardia: The Role of Imaging and Ablation in Diagnosis and Treatment.

A 50-year-old man presented with general fatigue on exertion. Investigations revealed tachycardia-induced cardiomyopathy induced by Wolff-Parkinson-White syndrome and atrial fibrillation. He was successfully treated with catheter ablation. Cardiac magnetic resonance imaging revealed that delayed enhancement throughout the left ventricle disappeared within 2 months after ablation. (Level of Difficulty: Beginner.).

Recurrent Cardiac Arrest With Negative Stress Test: An Unusual Presentation of Catecholaminergic Polymorphic Ventricular Tachycardia.

Catecholaminergic polymorphic ventricular tachycardia is a genetic disorder that causes ventricular tachyarrhythmias via increased release of intracellular calcium. The standard diagnostic measure is an exercise stress test that reveals ventricular ectopy. We present an extraordinary case marked by a normal stress test and no relation to exertion. (Level of Difficulty: Intermediate.).

Safety and Efficacy of Prehospital Diltiazem for Atrial Fibrillation with Rapid Ventricular Response.

INTRODUCTION: Atrial fibrillation (AFIB) with rapid ventricular response (RVR) is a common tachydysrhythmia encountered by Emergency Medical Services (EMS). Current guidelines suggest rate control in stable, symptomatic patients. PROBLEM: Little is known about the safety or efficacy of rate-controlling medications given by prehospital providers. This study assessed a protocol for prehospital administration of diltiazem in the setting of AFIB with RVR for provider protocol compliance, patient clinical improvement, and associated adverse events. METHODS: This was a retrospective, cohort study of patients who were administered diltiazem by providers in the Orange County EMS System (Florida USA) over a two-year period. The protocol directed a 0.25mg/kg dose of diltiazem (maximum of 20mg) for stable, symptomatic patients in AFIB with RVR at a rate of >150 beats per minute (bpm) with a narrow complex. Data collected included patient characteristics, vital signs, electrocardiogram (ECG) rhythm before and after diltiazem, and need for rescue or additional medications. Adverse events were defined as systolic blood pressure <90mmHg or administration of intravenous fluid after diltiazem administration. Clinical improvement was defined as a heart rate decreased by 20% or less than 100bmp. Original prehospital ECG rhythm interpretations were compared to physician interpretations performed retrospectively. RESULTS: Over the study period, 197 patients received diltiazem, with 131 adhering to the protocol. The initial rhythm was AFIB with RVR in 93% of the patients (five percent atrial flutter, two percent supraventricular tachycardia, and one percent sinus tachycardia). The agreement between prehospital and physician rhythm interpretation was 92%, with a Kappa value of 0.454 (P <.001). Overall, there were 22 (11%) adverse events, and 112 (57%) patients showed clinical improvement. When diltiazem was given outside of the existing protocol, the patients had higher rates of adverse events (18% versus eight percent; P = .033). Patients who received diltiazem in adherence with protocols were more likely to show clinical improvement (63% versus 46%; P = .031). CONCLUSION: This study suggests that prehospital diltiazem administration for AFIB with RVR is safe and effective when strict protocols are followed.Rodriguez A, Hunter CL, Premuroso C, Silvestri S, Stone A, Miller S, Zuver C, Papa L. Safety and efficacy of prehospital diltiazem for atrial fibrillation with rapid ventricular response. Prehosp Disaster Med. 2019;34(3):297-302.

Wolff-Parkinson-White syndrome with an unroofed coronary sinus without persistent left superior vena cava treated with catheter cryoablation.

Coronary sinus anomalies are rare congenital defects which are usually coexistent with a persistent left superior vena cava and may be associated with cardiac arrhythmias. We report an unroofed coronary sinus without persistent left superior vena cava diagnosed during a catheter ablation procedure for Wolff-Parkinson-White syndrome. Diagnostic and therapeutic options and outcomes are discussed. This condition is of relevance to electrophysiologists performing catheter-based procedures, as well as cardiologists implanting coronary sinus pacing leads, who may encounter this anomaly in their practice.

Radiofrequency catheter ablation of left-sided accessory pathways via retrograde aortic approach in children.

BACKGROUND: We aimed to analyze the results of retrograde aortic radiofrequency catheter ablation of left-sided accessory pathways in children. METHODS: Between January 2010 and September 2014, 25 children who underwent left-sided accessory pathway ablation with a retrograde aortic approach were evaluated retrospectively. RESULTS: The mean age of the patients was 11.09±3.71 years. Seventeen patients were male (68%). The mean procedure and fluoroscopy times were 71.54±21.05 min and 31.42±19.57 min, respectively. Radiofrequency energy was delivered with 41.38±15.32 W at 52.38±5.45 °C. Sixteen patients (64%) presented with manifest preexcitation and, 9 had concealed accessory pathways. The location of accessory pathway was left lateral in 16 patients, posteroseptal in 5, left anterolateral in 2, and left posterolateral and left posterior in the remaining 2. The acute success rate was 96%. The patients were followed for a mean of 16.68±18.01 months. There were 2 recurrences. No major complications were observed in the periprocedural period. One patient had groin hematoma, another one had transient severe headache and vomiting. Trivial mitral regurgitation was noted in a patient, which remained the same throughout follow-up. None of the patients developed new aortic regurgitation, pericardial effusion, or thrombi at the site of ablation. CONCLUSIONS: The retrograde aortic approach can be safely employed with a high success rate for ablation of left-sided accessory pathways in children.